Abstract: A system and method are described for a semi-permanent virtual circuit (SPVC) manager to manage a network of switches coupled together to form a semi-permanent virtual circuit. The SPVC manager considers connection resources internal to the network throughout the network when managing the SPVC. The SPVC manager uses either a static flow control window or a dynamically sized flow control window to manage pending connections within the network.

Abstract: A routing scheme generates a selection of precomputed routes that provide a wide range of available bandwidths while keeping delay (e.g., measure by cell transfer delay and cell delay variation), or cost, to a minimum, thus enabling high call rates at an overall lower call blocking rate. The routing scheme achieves this end by generating routes using a set of preconfigured bandwidth thresholds for pruning lower bandwidth links while least-cost optimizing on delay-based optimization functions, using for example, maximum cell transfer delay and maximum cell rate, or a cost-based function, using for example, administrative weight. The optimization function is determined during configuration by the selection of either cost-based or delay-based routing.

Abstract: A feedback control system for congestion prevention in a cell (packet) switching communication network is described. Congestion control is accomplished by controlling the transmission rate of bursty traffic in the presence of high priority, voice, low speed statistical, high speed deterministic and multicast data. Because bursty traffic is relatively insensitive to delay, adequate buffer capacity can be provided at the network nodes in order to minimize bursty data cell loss. By monitoring the buffer queue lengths at the nodes, a control signal can be generated at each intermediate node indicating the state of congestion. Excess queue length indicates incipient congestion while short queue lengths indicate excess capacity. Queue status is forwarded to the destination node where it is interpreted and sent back to the source node as a feedback rate control signal using a 2-bit code.

Abstract: A method of fair queuing and servicing cell traffic in a telecommunication node which interfaces with a telecommunication system including a multiplicity of nodes is described. The steps include placing cells of traffic are placed in a queue according to a hopcount associated with each cell of bursty traffic, the hopcount being representative of the number of nodes traversed by the associated cell. Cells of traffic within the queue are serviced according to their associated hopcount. The hopcount associated with each cell of traffic is incremented as each cell of traffic is serviced. Circuitry providing fair queuing and servicing of cell traffic in a telecommunication node which interfaces with a telecommunication system including a multiplicity of nodes is also described.